Chinese Hearthstone servers lost multiple days of progress in a tremendous setback.

The memes about Europe getting shortchanged may continue on, but over the weekend it was the Chinese Hearthstone server that really exemplified a worst case scenario.

During a scheduled maintenance, the Netease servers experience a power outage causing damage to the Hearthstone data. Due to this, the team scrambled to try and get everything fixed, but after 40 hours of toiling away, they realized it wasn't going to be possible.

The solution? Reset the entire server to what it was four days prior.

Up to 56 hours of progress prior to maintenance were completely lost including ranks climbed, packs opened, and quests completed. 

The joint decision between Blizzard and Netease, who runs Hearthstone in China, promised all gold/money spent during that time would be refunded, but of course, the damage was already done. Any cards unpacked were lost and users would have to hope to get similar cards once again.

"To clarify, we hope you understand that performing a roll-back is the absolute last resort," says the duo of companies according to a statement translated by Chua Zhihong, "we are deeply apologetic and regretful that we had to make this decision."

It continues, "Finally, we are fully aware that allowing this to happen was completely unacceptable. We will be reflecting on this, learning from this experience - including upgrading surveillance, better hardware protection - and do our utmost to ensure that similar incidents will not happen again. Thank you all for your understanding and support."

In it, they also promised compensation which was revealed today: 1000 gold and 15 packs, five from each of Old Gods, Classic, and Gadgetzan.

On an interesting note, players are investigating a correlation between the packs they opened prior to the reset to the ones they're opening now. There's currently a thread on the front page of Reddit trying to figure out if this is indeed the case. In short, the rarity of the cards seems to match what they were before the rollback.

Zhihong was in that thread as well, claiming that it appears as if rarities are tied to specific packs, giving a great example, "Guac Boi bought 10 classic packs during the rollback period and opened them all. He got 3 golden legandaries [sic] (Tirion, Ragnaros, Jaraxxus) on his 9th pack and didn't want to ever go outside any more." He continues, "After the roll back (and 30 drinks), he decided to open MSG packs instead and got zero legendaries from them. However, 9 brawls and 9 weeks later, he opened a 3 golden legendary pack (Pagle, Pagle, Millhouse) again after Webspinners #69."

Though Game Director Ben Brode has confirmed that cards are determined when you first open the pack, it's entirely possible that the rarity itself is determined beforehand.

If true it's a curious revelation on how Hearthstone's packs function, though we aren't sure what good this knowledge actually does for you outside of when Blizzard ends up having to roll back servers. Fortunately, this is the first time it's ever occurred even if it did happen to the most populous region.